Zinc glycine chelate absorption characteristics in Sprague Dawley rat

This study was conducted to investigate absorption characteristics of zinc glycine chelate (Zn–Gly) by evaluating tissues zinc status and the expression of zinc transporters in rats. A total of 24 male rats were randomly allocated to three treatments and administered either saline or 35 mg Zn/kg body weight from zinc sulphate (ZnSO₄) or Zn–Gly by feeding tube separately. Four rats per group were slaughtered and tissues were collected at 2 and 6 h after gavage respectively. Our data showed that Zn–Gly did more effectively in increasing (p < 0.05) serum zinc levels, and the activities of serum and liver alkaline phosphatase (ALP) and liver Cu/Zn superoxide dismutase (Cu/Zn SOD) at 2 and 6 h. By 2 h after the zinc load, the mRNA and protein abundance of intestinal metallothionein1 (MT1) and zinc transporter SLC30A1 (ZnT1) were higher (p < 0.05), and zinc transporter SLC39A4 (Zip4) lower (p < 0.05) in ZnSO₄ compared to other groups. Zinc transporter SLC39A5 (Zip5) mRNA expression was not zinc responsive, but Zip5 protein abundance was remarkably (p < 0.05) increased in ZnSO₄ 2 h later. Overall, our results indicated that in short‐term periods, Zn–Gly was more effective in improving body zinc status than ZnSO₄, and ZnSO₄ did more efficiently on the regulation of zinc transporters in small intestine.     

Investigations on iron bioavailability of different sources and supply levels in piglets

Two experiments were conducted to investigate the iron bioavailability of different sources and supply levels in piglets. In experiment 1, the influence of feeding an iron deficient basal diet or the basal diet supplemented with 28 ppm Fe either in form of Fe-chelate, crystalline Fe-glycinate, or Fe-sulphate on apparent iron digestibility and on blood parameters was determined. In experiment 2, a dose-response approach was used to determine the effects of supplementing an iron-deficient basal diet with 30, 60, or 90 ppm of Fe either in form of crystalline Fe-glycinate or Fe-sulphate on digestibility of Fe, growth and blood parameters. In experiment 1, comparison of iron sources revealed a tendency (0.05 < p < 0.1) for a higher Fe digestibility from Fe-glycinate (40.9%) compared with Fe-chelate (30.8%) or Fe-sulphate (30.7%). Fe-balance was higher (p < 0.05) for Fe-glycinate compared with Fe-sulphate but iron balance was similar for iron sulphate and iron chelate. Those results, however, were not reflected in data of blood parameters. In experiment 2, iron digestibility, blood parameters and performance were significantly (p < 0.05) influenced by iron supply. Effects of iron source on digestibility of iron were lower than observed in the first experiment.     

ICP—AES测定食品中内源性钛和外源性二氧化钛

采用微波消解法,通过不同的酸体系消解样品分别测定包含二氧化钛的总钛和不包含二氧化钛的内源性钛,总钛减去内源性钛即得到外源性二氧化钛,其中HNO3＋HCl＋HF＋H2O2（5／1／1／3,V/V/V/V）酸体系（能溶解二氧化钛）用于测定总钛,HNO3＋HCl＋H2O2（5/1/3,V/V/V/V）酸体系（不能溶解二氧化钛）用于测定内源性钛。结果表明,食品中的二氧化钛加标回收率为94．6％-106．7％,RSD为1．0％-5．3％,二氧化钛方法最低检出限为0．22mg／kg。该检测方法克服了国家标准方法仅测定总钛的局限性,是定性、定量测定食品中二氧化钛较为实用的方法。     

Reduction of Titanium Oxide and Thickening of Blast Furnace Slag Bearing Higher Titania

The slag samples that have some titanium oxide reduction grade are reduced with blast furnace slag taken from Pan Zhi Hua Iron & Steel (Group) Co. in site. Then the viscosity and free running temperature of slag samples were measured in laboratory. With the increasing of reduction grade the viscosity and free running temperature of slags would have rising tendency. The mineral structure of the samples is observed in optical microscope, and quantitative analysis of TiC, TiN in the slag samples is made with image analysiser. The results show that the thickening of titanium slag has relationship with the amount of TiC, TiN, which was reduced from titania. So the usage of titanium oxide reduction grade as the index of thickening in blast furnace process is reasonable, and which could represent characteristic of the blast furnace smelting iron ore bearing titanium and vanadium.     

有益元素钛的植物营养学研究进展

钛是作物生长的有益元素,对作物生长发育具有重要作用。笔者综述了土壤和植物中钛的含量、分布与影响因素、钛的生理生化功能及钛在农业上的应用等研究进展,并在此基础上提出加强土壤中钛的形态及生物有效性,钛施入土壤后的形态转化,作物有效性钛形态及测定方法,植物对钛的吸收、运输、转化等研究相关发展建议。     

Green Synthesized Zinc-Glycine Chelate Enhances Antioxidant Protection of Pistachio under Different Soil Boron Levels

Zinc (Zn) and boron (B) disorders are common nutritional stresses in arid and semi-arid regions. In the current study, effectiveness of soil Zn amendment (0, 5.0, 10.0, and 20.0 mg kg^–1 soil) using Zn-glycine chelate (Zn-Gly), a novel Zn-fertilizer, which is especially synthesized for application in calcareous soils in arid and semi-arid areas, was evaluated under different soil B levels (0, 2.5, 5.0, 10.0, and 20.0 mg kg^–1 soil) for a 100-day period. Pistachio, the most valuable crop grown under arid conditions, was used as the model plant. Measurement of electrolyte leakage, H₂O₂, and malondialdehyde indicated the incidence of oxidative stress in the leaves of pistachio under low and high soil B concentrations. In addition, B stress caused a significant increase in lipoxygenase activity in the leaves. Plants treated with 5.0 mg B kg^–1 soil showed the lowest oxidative stress injuries and lipid peroxidation. Application of 5.0 mg Zn kg^–1 soil significantly alleviated the B stress damages, however, the ameliorative effect of Zn was vanished by application of higher Zn concentrations. Evaluation of the antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], or ascorbate peroxidase [APX]) and non-enzyme antioxidants (ascorbate and phenolic compounds) revealed that the protective effects of Zn-Gly against B stress are due to enhancement of cell antioxidant defense. In conclusion, application of Zn-Gly for reducing oxidative stress pressure in pistachio plants grown under B disorder was suggested.     

二氧化钛/壳聚糖/丙烯酸复合水凝胶的原位交联及性能

壳聚糖基复合材料在水凝胶领域应用广泛,但其制备过程中通常需要有毒性的化学交联剂和经过繁琐的化学修饰等过程。将壳聚糖、丙烯酸和钛酸四丁酯共混,在遇水后,通过钛酸四丁酯的原位水解形成的纳米二氧化钛作为物理交联剂,一步法制备复合水凝胶,过程简单且无需化学交联剂。在此复合水凝胶中,纳米二氧化钛作为交联剂和光催化剂,丙烯酸可以提高壳聚糖的吸水性,同时丙烯酸和壳聚糖表面的羟基和氨基等基团又可以增强二氧化钛的光催化性能。利用X射线衍射、傅里叶红外光谱、扫描电镜和透射电镜等考察其形貌与结构等特征,并通过吸水试验和亚甲基蓝的光降解试验测试了其溶胀及光催化性能。结果表明:该复合水凝胶内部为多孔结构,粒径约为5~12 nm的二氧化钛均匀分散在复合水凝胶中,无团聚现象。该复合水凝胶材料具有优良的吸水性,其饱和吸水率约为1500%,在模拟自然光下对亚甲基蓝有较好的光催化降解效果。以上结果表明该材料在污水处理领域具有一定的应用前景。     

母猪饲粮中添加蛋氨酸铁螯合物对预防仔猪贫血的影响

本试验研究了妊娠母猪饲粮中添加蛋氨酸铁螯合物对仔猪血液生化指标、生长速度和预防仔猪贫血的影响。试验结果表明在母猪妊娠第９３天至哺乳２１天饲粮中添加６０ｍｇ／ｋｇ蛋氨酸铁螯合物,仔猪初生时不注射铁剂组的血红蛋白浓度较对照组仔猪提高１５．６７Ａ％（１０．７８：９．３２ｇ／１００ｍｌ）,但差异不显著（Ｐ＞０．０５）：７、２１日龄的血红蛋白浓度为１０ｇ／１００ｍｌ左右,铁营养处于适宜水平。试验组仔猪初生时的红细胞含量显著高于对照组（Ｐ＜０．０１）,但７、２１日龄时则低于对照组（Ｐ＜０．ｏ１,Ｐ＜０．０５）;仔猪的初生重、日增重和３５日龄断奶窝重与对照组相似（Ｐ＞０．０５）。仔猪血液生化指标和体重变化说明蛋氨酸铁螯合物可有效地防止仔猪缺铁性贫血的发生。     

不同复合氨基酸铁、锌络合物添加量对肉仔鸡生产性能的影响

为研究不同复合氨基酸铁、锌络合物的添加量对肉仔鸡生产性能的影响。选取360只体重相近的1日龄AA商品代雏鸡,采用单因子试验设计,随机分成6组,每组3个重复,每个重复20只鸡;对照组(CON组)饲喂基础饲粮,铁、锌来源为七水硫酸亚铁和无水硫酸锌,添加量都为100 mg/kg;其他5组设为试验组,铁、锌来自复合氨基酸络合物,铁和锌的添加量为25(Ⅰ组)、50(Ⅱ组)、75(Ⅲ组)、100(Ⅳ组)、125(Ⅴ组)mg/kg。在21和42日龄时进行采血和屠宰,测定生产性能、屠宰性能和不同组织中铁、锌的浓度。结果表明:1)21日龄试验Ⅱ组平均体重显著高于CON组(P0.05);42日龄试验Ⅴ组平均体重显著高于CON组(P0.05)。2)22～42日龄和1～42日龄试验Ⅴ组平均日采食量显著高于CON组(P0.05);22～42日龄试验Ⅴ组平均日增重显著高于CON组(P0.05),各组间料重比无显著差异(P0.05)。3)21日龄试验Ⅱ组胸肌率显著高于对照组(P0.05),42日龄试验Ⅴ组胸肌率显著高于CON组(P0.05),其他各组屠宰性能指标差异不显著(P0.05)。4)试验Ⅲ组和Ⅴ组肝脏中的铁、锌浓度显著高于对照组(P0.05)。因此,在基础饲粮中添加氨基酸铁、锌络合物可以提高肉仔鸡的生产性能,增加对铁、锌的有效利用,间接减少对环境的污染;并且试验中添加50和125 mg/kg的2组效果较好,但考虑低能减排问题还是以50 mg/kg的添加量最佳。     

椰子球蛋白多肽-亚铁螯合物的制备工艺

为提高椰子加工副产物的利用, 对椰子球蛋白进行限制性水解制备多肽,并采用Sephadex G-25凝胶柱层析对多肽进行纯化,然后以椰子球蛋白多肽为原料与亚铁离子反应制备肽-亚铁离子螯合物。重点分析水解度、温度等因素对椰子球蛋白多肽亚铁离子络合能力的影响,并优化制备工艺。结果表明,用碱性蛋白酶结合风味蛋白酶制备的多肽的水解度最高（14.71%）,产物的亚铁离子螯合能力也最高（24.66%）;Sephadex G-25凝胶柱层析中分离出3个多肽组分,其中组分C的络合能力最高（28.67%）;椰子球蛋白多肽C螯合亚铁离子最佳条件是多肽浓度1 mg/mL、40 ℃、 pH 7.0、亚铁离子浓度0.5 mg/mL、时间0.5 h,此时螯合率为30.67%。荧光光谱、红外光谱等分析表明,椰子球蛋白多肽通过氨基、羧基和亚甲基与亚铁离子配位而形成螯合物。研究结果表明,用椰子球蛋白多肽为原料制备肽-亚铁螯合物切实可行,该螯合物可以应用于功能食品中来改善铁营养缺乏。